Black Sabbath is an Englishheavy metalband. They are considered to be an influential heavy metal band which helped start the genre in the late 1960s and early 1970s. They have sold over one hundred million albums worldwide. The original line up was Ozzy Osbourne (vocals), Tony Iommi (guitar), Terence "Geezer" Butler (bass) and Bill Ward (drums).[1]

Black Sabbath formed in 1968. The band was originally named Earth and they played blues-rock music. In the band's early days Tony Iommi had a work accident that cut off the tips of his middle and ring finger on his right hand. He began tuning his guitar lower to slacken his strings to make playing easier on his wounded fingers. The result was a darker, deeper tone to his guitar sound which the band felt made their music sound dark and scary. The music also featured unusual key changes and time signatures (metre). They released their first album Black Sabbath in 1970. Their most successful single, titled "Paranoid", produced by Rodger Bain, came off their second album of the same name, also released in 1970.

The third album in 1971 was called 'Master of Reality' and sounded even more doomy than the previous two albums. After that album, the band members became addicted to cocaine, and wrote a song called 'Snowblind' to celebrate this. Their fourth album in 1972 was meant to be named after the song, but their label did not want to release an album named after an illegal drug, so they gave it the name 'Black Sabbath Vol. 4' instead. Their fifth album 'Sabbath Bloody Sabbath' came out in 1973 and was the first of their albums to get good reviews from critics, although their opinion of the first four albums also changed to become much more positive over time.

In 1975, Sabbath released 'Sabotage', which featured some longer more progressive songs, and had a less doomy feel. This change in direction continued with 1976's 'Technical Ecstasy' which received mixed reviews. Ozzy lost some interest in the band and left for a short time, but decided to rejoin in time for an eighth album, 'Never Say Die!' which received bad reviews.

Ozzy Osbourne was fired from the band in 1979 because of his drug and alcohol addiction. American vocalist Ronnie James Dio was hired to replace him. The band recorded two studio albums and one live album with him. The first studio album of the two, 'Heaven And Hell' was considered a return to success and musical form, with 'Mob Rules', recorded with drummer Vinny Appice after Bill Ward left, also getting a good reaction. Dio and Vinny parted with Black Sabbath in 1982 over different musical ideas. Bill rejoined and the band hired Deep Purple singer Ian Gillan for the critically unsuccessful 'Born Again'.

Over the next few years after Bill left again along with Geezer, Iommi would hire several different singers to front the band, such as Glenn Hughes and Tony Martin, along with a variety of bassists (Dave Spitz, Neil Murray etc.) and drummers (Eric Singer, Cozy Powell etc.). Many of the albums released during this time were not meant to be released as Black Sabbath, with Tony Iommi wanting them to be his solo albums.

In 1991 Ronnie James James Dio and Vinny Appice rejoined the band again for one album and tour. After that, Tony Iommi once again hired Tony Martin alongside other different musicians. In 1997 the original line up reformed and continued to perform occasionally until 2006, when the band members were busy focusing on individual projects.

In 2005, Black Sabbath were inducted into the "UK Music Hall of Fame". In 2006 the band were inducted into the Rock and Roll Hall of Fame.

In 2011, the original line up announced they were getting back together to tour and record a new album. However, Tony Iommi was diagnosed with cancer, forcing the band to cancel most tour dates, and Bill Ward left after being unsatisfied with the contract. Tony Iommi has since been recovering, and Sabbath hired drummer Tommy Clufetos to tour with them. However, Brad Wilk is drumming on the new album, which is called '13' and was released in June 2013.